Implementation of Intermediate-Band Solar Cells using Multi-Band Semiconductors

0932905该奖项是根据2009年美国复苏和再投资法案（公法111-5）资助的。该项目旨在充分展示基于最近发现的多波段半导体合金AlyGa1-yAs1-xNx的中波段太阳能电池。该研究将针对光伏科学和技术中的基本问题进行。能否克服单p-n结光伏效率的Shockley-Queisser极限？通过电子结构工程，可以在单相材料中实现太阳能电池运行的哪些新范式？该计划的更广泛目标是在合作环境中培养本科生和研究生以及博士后研究人员，将能源科学和政策的研究创新和概念转移到课堂上，并吸引周围社区，特别是小学生，参与围绕能源可持续性和技术作用的讨论和学习。知识价值。如果成功，这项研究计划将导致有史以来最高的光伏效率，超过35%，在单结，单相太阳能电池。这样的成就将对基于中间波段的太阳能电池的理解产生重大的进步-一种有前途的设备架构，已经被预测但尚未证明可以产生高能量转换效率，因此，潜在的成本比高效的多结太阳能电池低得多。将多波段半导体AlyGa1-yAs1-xNx外延集成到传统p-n结的中波段太阳能电池的演示将促进半导体薄膜生长和器件加工的创新。将获得有关多波段半导体材料物理的新知识。这种多波段系统与广谱光子的相互作用尚未得到充分的表征和理解。因此，所提议的活动的很大一部分将致力于阐明这种新型材料系统中载流子的光物理和热力学。更广泛的影响。利用光伏发电将太阳光转化为电能，不仅激发了科学家、工程师和技术人员的想象力，也激发了广大公众的想象力。太阳能电池研究提供了令人兴奋的机会，让未来的能源科学和技术创新者在各个层面上参与进来。加州大学伯克利分校拟议的研究和教育项目将为旧金山湾区从小学到博士后水平的各个阶段的学生提供宝贵的培训和学习机会。作为一个新兴产业，能源技术将经历巨大的增长，使多样性的注入现在是一个关键的行动。拟议的外联活动的目标是通过培训和指导来自不同背景的学者来促进能源部门的多样性。

0932905WuThis award is funded under the American Recovery and Reinvestment Act of 2009 (Public Law 111-5).SummaryThe project is aimed at the full demonstration of an intermediate-band solar cell based on the recently discovered multi-band semiconductor alloy AlyGa1-yAs1-xNx. The research to be undertaken targets fundamental questions in photovoltaics science and technology. Can the Shockley-Queisser limit of photovoltaic efficiency in a single p-n junction be overcome? What new paradigms in solar-cell operation can be realized in a single-phase material through electronic structure engineering? The broader objectives of this program are to train undergraduate and graduate students as well as postdoctoral researchers in a collaborative environment, to transfer research innovations and concepts in energy science and policy to the classroom, and to engage the surrounding community, specifically elementary school children, in discussions and learning around energy sustainability and the role of technology. Intellectual Merit. If successful, this research program will lead to the highest ever photovoltaic efficiency, exceeding 35%, in single-junction, single-phase solar cells. Such an achievement would produce significant advancements in the understanding of solar cells based on intermediate bands - a promising device architecture that has been predicted but not yet demonstrated to yield high energy conversion efficiency, hence, potentially at much lower cost than highly efficient multi-junction solar cells. Demonstration of an intermediate-band solar cell using the multi-band semiconductor AlyGa1-yAs1-xNx epitaxially integrated into a conventional p-n junction will promote innovations in semiconductor thin-film growth and device processing. New knowledge concerning the materials physics of the multi-band semiconductors will be gained. The interaction of such a multi-band system with broad-spectrum photons has not been fully characterized and understood. Therefore, a significant portion of the proposed activities will be devoted to elucidating the photo-physics and thermodynamics of charge carriers in this novel materials system.Broader Impacts. The transformation of sunlight into electrical energy using photovoltaics has captured the imagination of not only scientists, engineers and technologists but also the public at large. Solar cell research provides exciting opportunities to engage future innovators in energy science and technology at all levels. The proposed research and education program at U.C. Berkeley will provide invaluable training and opportunities for learning to students at all stages, from elementary school to the postdoctoral level, in the San Francisco Bay Area. As an emerging industry, energy technology will experience tremendous growth, making the infusion of diversity now a critical action. The proposed outreach activities will be targeted to promoting diversity in the energy sector by the training and mentoring of scholars from diverse backgrounds.